Footwear device for moving around on walls made of perforated cladding plates

ABSTRACT

Disclosed is a footwear device for moving around on walls made of perforated plates, having an innerboot secured to a sole made of flexible plastics material, extending along a longitudinal axis from a heel to a tip, the sole having a semi-rigid plate, known as a core, embedded in the thickness of the sole. The core is designed to receive one or more rigid fingers that are able to pass into a hole in the wall made of perforated plates, the finger extending along the longitudinal axis and protruding from the front of the sole.

The invention relates to a footwear device for moving around on walls made of perforated cladding plates, in particular on vertical walls.

The term moving around (and its derivatives: movement around etc.) is understood to mean being mobile or being in an immobile posture on or along the walls in question.

From e.g. patent no. EP 2 111 492 of the applicant, a device is known for cladding the roof and/or walls of a building from the outside by means of perforated metal sheets. However, if, in order to install such cladding, the use of scaffolding is justified, the placement of scaffolding is very expensive when carrying out minor work on this cladding, such as attaching a fitting, replacing a sheet metal plate, etc.

Furthermore, during such work, it is useful to procure professional footwear, named safety footwear, in order to avoid accidents. Such footwear is known e.g. from EP 0 013 197, comprising an upper enclosing the foot and a sole fixedly attached to the upper. The sole is formed by injecting a synthetic material around a metal plate which is thus embedded in the sole. There are numerous models of professional footwear adapted to numerous activities but none is specifically adapted to work on a building comprising perforated plate cladding.

In this document, perforated cladding is understood to mean cladding made of plates comprising perforations of various shapes, generally round or square. The cladding plates can commonly be made of metal (steel, aluminium, etc.), in which case they are referred to as perforated metal sheets but can also be made of synthetic materials, of wood, or be based on strips or particles of wood, with or without resin.

The present invention aims to provide a footwear device such as an item of professional footwear or an overshoe adapted to movement and work on buildings covered with perforated plates.

The invention also aims to provide such a footwear device permitting the safety of persons working on such buildings to be increased.

The invention also aims to provide such a footwear device which makes it possible to dispense with scaffolding or a ladder in order to carry out work on such buildings.

The invention also relates to a footwear device which makes it possible to adopt a safe working position even on a vertical wall.

In order to do this, the invention relates to a footwear device for moving around on walls made of perforated plates, comprising an upper fixedly attached to a sole of flexible synthetic material, extending along a longitudinal axis from a heel to a toe, said sole comprising a semi-rigid plate, named core, integrated into the thickness of the sole, characterised in that said core is adapted to receive at least one rigid finger able to pass into a corresponding hole in the wall made of perforated plates, each finger extending at least partially along the longitudinal axis and protruding towards the forward part of the sole.

In this document, a rigid finger is understood to be a protruding element, the size and/or material of which are such that the element will not flex under the effect of a moment representing the weight of a user (of the order of 1000 N) applied at a distance at least equal to the length of the sole (e.g. of the order of 50 cm), or a torque of about 500 mN. Such a rigid finger can also be produced e.g. by means of a cylindrical steel rod, 3 to 10 mm in diameter and 10 to 30 mm in length, as long as the forces applied do not exceed the elastic limit of the material.

By virtue of this rigid finger placed at the end of the shoe which passes into the perforations in the wall made of perforated plates, it is possible to be supported on a vertical wall. The rigid finger is fixedly attached to the core of the sole, thus the force or more precisely the torque involved in hooking onto the wall is distributed throughout the sole. The diameter of the rigid finger is adapted to the dimensions of the perforations so as to permit easy insertion thereinto without in so doing allowing excessive play between the finger and the edge of the perforation which would cause an increase in the angle between the axis of the finger and that of the perforation from which the finger is braced in the perforation. Of course, in order to facilitate the insertion of the finger into the perforation in the wall made of perforated plates, the end of the finger may be conical or rounded. In the same way, the finger can be slightly curved downwards to prevent it becoming unhooked by sliding when the foot is horizontal but its curvature must also permit unhooking by inclining the foot backwards by an angle of 5° to 10°.

Advantageously and in accordance with the invention, each finger is removably mounted in the core of the sole. In this way it is possible to choose a finger of a size appropriate to that of the perforations in the metal sheet. In order to do this the finger can be mounted by any fixing method in a receiver fixedly attached to the core of the sole, e.g. by screwing, along its axis, a cylindrical threaded finger in a tapped receiver.

Advantageously and in accordance with the invention, the finger is fixed directly to a prismatic receiver fixedly attached to the core. This embodiment is simpler and more economical.

Advantageously and in accordance with the invention, the finger is fixed in a receiver fixedly attached to the core by a conical shank comprising a flat for orientating the finger. The conical shank permits excellent centring of the axis of the finger with respect to the longitudinal axis of the sole, rapid and easy placement and a very secure hold for the cone in its receiver. Furthermore, the replacement of one finger by another of a diameter better suited to the size of the perforations in the wall is easily effected by inserting a cone driver in an orifice provided perpendicularly to the sole on the lower face thereof and issuing at the rear of the receiver. In the case where the finger used is slightly clawed to improve engagement in the perforation, a flat is provided on the cone and on its receiver to orientate the curvature of the finger in the right direction.

Advantageously and in accordance with the invention, the device comprises a plurality of fingers removably and adjustably mounted on a support fixedly attached to the core of the sole. It may be useful, in improving the lateral stability of the user of the device, to be able to provide two or three fingers having a spacing between them such that the device cannot pivot in a horizontal plane when it is anchored in the wall. These fingers are mounted on a support in the form of a rectangular plate (for two fingers) or triangular plate (for three fingers), the support being fixed to the core of the sole. Advantageously, in order to be able to adapt the device to different perforated plates having variable centre distances and/or diameters for the holes, each finger is removable and can be replaced by a finger better suited to the diameter of the holes and/or displaced on the support to adjust the position of the fingers according to the centre distance of the holes in the perforated plate. In the same way as for a single finger, advantageously and in accordance with the invention, the support is fixed in a receiver fixedly attached to the core by a conical shank comprising a flat for orientating the support. The flat also makes it possible to prevent rotation of the support about the longitudinal axis of the sole.

Advantageously and in accordance with the invention, the core is also suitable for forming, at the heel, a transverse housing orthogonal to the longitudinal axis, issuing on both sides of the sole. At the end of the sole opposite the finger, i.e. at the heel and substantially in the middle thereof along the longitudinal axis of the sole, a transverse housing in the form of a tubular passage, integral with the core of the sole, extends therethrough from one side to the other in the plane of the sole and orthogonally to the longitudinal axis thereof. This housing makes it possible to insert a shaft emerging at both sides of the sole in order to fix thereon a member permitting the heel to be supported when the footwear device of the invention is used in a static position (especially during repair work) on a vertical wall.

Advantageously and in accordance with the invention, the device comprises a stirrup comprising two branches connected by an arch, said branches being respectively articulated on both sides of the sole on a shaft extending through the transverse housing, the arch of said stirrup extending over a front of the upper. In order to support the heel in a static position, a stirrup connected to the heel of the footwear device passes around the instep of a user to return to the forward part of the shoe. In the inoperative position, the stirrup rests against the front and is held thereon, if necessary, by an elastic strap. The branches of the stirrup can be fixed to the ends of a straight shaft placed in the through-going housing or can cooperate with the eyelet-like ends of a shaft bent into two parts.

Advantageously and in accordance with the invention, the device comprises a hook articulated on the arch of the stirrup and adapted to hook into a hole in the wall made of perforated plates. In a static position on a wall, the hook and the arch are deployed and the hook is inserted into a perforation in the wall. Advantageously and in accordance with the invention, the stirrup and the hook have a combined length such that the sole is held substantially perpendicular to a wall made of perforated plates when the finger is inserted in a first hole in the metal sheet and the hook is hooked into a second hole vertically in line with the first.

Advantageously and in accordance with the invention, the device comprises two lateral tie rods respectively fixed to each end of the shaft and adapted to be tensioned between said end and a hole in the wall made of perforated plates, located substantially in a plane of the sole. By virtue of these lateral tie rods, even if the footwear device of the invention uses only a single finger at the toe of the sole, any lateral movement of the heel is prevented, thus ensuring a high level of stability for the user. These lateral tie rods each comprise a hook analogous to the hook articulated on the arch of the stirrup. For greater convenience, these hooks are fixed to each end of the shaft extending through the sole by a flexible cable, which also makes it possible to store the hooks along the sides of the sole.

Advantageously and in accordance with the invention, the lateral tie rods have a length making it possible to fix their end in a hole located at a distance between a half-length and a length of the core with respect to the longitudinal axis of the sole. By virtue of this arrangement, the heel of the sole is placed at the top of an isosceles (if not an equilateral) triangle defining a substantially horizontal plane in which the sole is kept orthogonal to the wall.

Advantageously and in accordance with the invention, the sole comprises an external face, named wear sole, fitted with studs having a recess, which are adapted to hold the device by a suction effect on a wall made of perforated plates having an inclination permitting movement on the wall without use of the rigid finger. Thus, for movement around a flat or slightly inclined roof for which it would be inconvenient to use the insertion of the rigid finger into the perforations in the wall, the studs moulded in the flexible (elastomer-type) synthetic material of the sole form suction cups permitting sufficient adherence on the wall. The position and distribution of the studs on the sole are preferably such that not all the studs are located facing the perforations in the wall at the same time. The shape of the recess in the studs is preferably conical but could also be of any shape (e.g. hemispherical, tapered, pyramidal, etc.) adapted to generate a suction effect.

Advantageously and in accordance with the invention, the sole comprises, at the heel, at least one stud, the recess in which is smaller so as to reduce the suction effect of said stud in order to facilitate detachment of the sole under the effect of traction. Thus, in normal forwards walking motion, the heel rises first, the stud(s) with a lower suction effect is (are) easily detached and draw the other studs with them in succession.

Advantageously and in accordance with the invention, the studs are removable and are fixed by screwing in tapped housings integral with the core. It is thus possible to choose the type of studs, the hardness thereof, etc. according to the intended use (e.g. flexible studs to move over rigid planar surfaces, hard, long studs or even metal studs to move over an icy surface).

Advantageously and in accordance with the invention, the sole has at least one longitudinal stiffener extending below the core from the toe to the heel of the sole. The stiffener can be fixed, formed e.g. of one or two angle bars welded under the core and embedded in the wear sole in parallel with the longitudinal axis of the sole. In a preferred manner, the stiffener is removable and is in the form of a rod extending through the receiver for fixing the finger or the finger support. The stiffener can thus be fixedly attached to the Morse taper serving to fix the finger or support and to emerge at the heel of the sole in order to be fixed at that location by a pin and, if necessary, to serve to eject the Morse taper.

Advantageously and in accordance with the invention, the upper forms an overshoe and comprises a lacing arrangement suitable for keeping a shoe firmly in the upper. The footwear device in accordance with the invention can thus be offered in a number of variations, either a simple work shoe in which the foot is held by a conventional lacing arrangement, or an overshoe able to receive a foot already wearing a shoe. In the latter case, it is useful to provide a lacing arrangement adapted to permit a wide variety of forms of shoe to be held. This lacing arrangement can comprise lacing of the facings as well as lacing permitting the circumference of the ankle to be adapted, etc.

The invention also relates to a footwear device characterised in combination by all or some of the features mentioned above or below.

Other aims, features and advantages of the invention will become apparent in view of the following description and the accompanying drawings, in which:

FIG. 1 illustrates a perspective view of a footwear device in accordance with the invention,

FIG. 2 illustrates a simplified perspective view, with the upper removed, of a footwear device in accordance with the invention showing its use on a vertical wall,

FIG. 3 is a partial cross-sectional view of the device in accordance with the invention detailing the forward part of the sole,

FIG. 4 is a partial cross-sectional view of the device in accordance with the invention detailing the rear part of the sole,

FIG. 5 illustrates a perspective view of a footwear device in accordance with a variation comprising a plurality of fingers mounted on a support,

FIG. 6 is a perspective view of a support comprising three fingers and showing the means for adjusting the position of these fingers,

FIG. 7 is a perspective view of a support comprising two fingers and showing the means for adjusting the position of these fingers,

FIG. 8 is a view similar to FIG. 2 showing the user of lateral tie rods,

FIG. 9 is a longitudinal cross-sectional view of the sole of the device in accordance with the invention showing the stiffener,

FIG. 10 is a view of a detail of a longitudinal cross-sectional view of the forward part of the sole showing the device for fixing the removable studs.

The footwear device 1 of the invention illustrated in FIG. 1 comprises an upper 2 comprising a heel 24 and a front 25 fixedly attached to a sole 3. The sole 3 comprises a semi-rigid plate, named core 5, (FIGS. 3 and 4) in particular of steel, and generally integrated into the thickness of the sole between a lower part in contact with the ground, named wear sole 18, and an upper layer, named first layer, isolating the interior of the upper from the core 5. Thus the core 5 can be placed inside the upper 2 and contribute to the fixing thereof to the sole or can be embedded in the thickness of the sole during injection thereof. This core 5 makes it possible to prevent the sole being perforated e.g. if a nail is stepped on.

The device 1 has an orientation defined by a longitudinal axis 22 extending from the heel 24 to the toe of the shoe. The footwear device 1 also comprises characteristic elements which make it possible to adapt it to use on walls made of perforated plates. In particular, at the forward end of the sole 3, a rigid finger 4, generally of metal and more particularly of steel, protrudes with respect to the sole 3 along the longitudinal axis 22. The finger 4 is fixedly attached to the core 5 of the sole 3. As described hereinunder, the finger 4 is adapted to pass into holes 28 (FIG. 2) of a wall 13 made of perforated plates.

FIG. 5 illustrates a variation of the device 1 in which the single finger 4 has been replaced by a support 30 of a substantially rectangular shape fixed orthogonally to the longitudinal axis 22. The support 30 comprises two fingers 4 fixed respectively to the longitudinal ends of the rectangle. In an advantageous manner, since the spacing between the two fingers 4 is greater than a half-length of the sole 3, the sole can no longer pivot about a vertical axis parallel to the wall passing through the toe of the sole. Thus the lateral stability of the user's foot is assured.

FIGS. 6 and 7 illustrate embodiments of the support 30. FIG. 6 illustrates a support 30 in the form of a triangle, preferably an equilateral triangle, comprising a finger 4 at each corner. The support 30 also comprises, at each corner, elongate holes 31 into which threaded rods 32 pass, these rods comprising at least one flat 32 a making it possible to prevent rotation of the finger 4. The position of the finger 4 can be adjusted by sliding the threaded rod 32 in the elongate hole 31. The finger 4 is then fixed by tightening a nut 32 b on the plate forming the support 30. It is thus possible to adapt the position of the fingers 4 to the spacing of the holes in the wall made of perforated plates. In the embodiment illustrated in FIG. 7, the support 30 is formed of two bent strips 33 supported against one another and fixed to the core 5 of the sole 3 by a screw 34. The two bent strips 33 can move with respect to one another by virtue of an elongate hole through which the screw 34 passes.

The sole 3 also comprises a transverse housing 9 extending through the sole from one side to the other in the plane thereof and orthogonally to the longitudinal axis 22 at the heel 24. This transverse housing 9 is adapted to receive a shaft 10 formed in the illustrated example by two bent half-shafts connected within the housing 9, e.g. by screwing, and comprising an eyelet 21 at their outer end.

The wear sole 18 comprises studs 16, the shape and function of which will be detailed below in relation to FIGS. 4 and 10.

The footwear device 1 can be offered in the form of an overshoe adapted to enclose an existing shoe or even shaped as a shoe which can be used directly. In the first case, it is not necessary to distinguish a right foot and a left foot, the upper 2 being able to be symmetrical with respect to the longitudinal axis 22. The upper 2 can be produced of any material suitable for work shoes, e.g. leather, suitable synthetic material and/or strong canvas. The upper 2 is provided with one or a plurality of laces permitting the upper to be adjusted. In the example illustrated in FIG. 1, the upper 2 has a first lace 19 threaded through eyelets fixedly attached to quarters of the shoe and permitting adjustment of the upper on the user's instep, a second lace 20 threaded through a hem around the ankle to permit adjustment of the upper thereto. These two laces can cooperate e.g. by passing the lace 19 within loops belonging to the lace 20 after adjustment of the upper, the tightening of the lace 19 causes complementary tightening of the lace 20. Of course, the lace 20 can also be replaced by a strap device 20′ as shown in FIG. 5. A third lace 19′ can be used when the footwear device is an overshoe. This third lace 19′ is threaded through a hem along the quarters of the device and is tightened at the top of the instep to close the device along the instep.

Reference is made to FIG. 2 to detail the operation of the footwear device of the invention. This figure illustrates a footwear device 1 in which the upper 2 has been removed to simplify the view. The sole 3 is disposed facing a wall 13 made of perforated plates. The finger 4 is embedded in a hole 28 in the wall 13 and makes it possible to be supported thereon. In a climbing phase, e.g. on a vertical or strongly inclined wall 13, the user inserts the finger 4 of one of the shoes in a hole in the wall, bears thereon in order to advance and then inserts the finger of the other shoe in another hole located several rows above (or rather below, when descending) and changes his foothold to the other side to progress further. Of course, the user can be assisted by using his arms, hooking the fingers of his hand or hooks held in the hand into the holes in the wall 13.

In the static position, the footwear device 1 comprises means making it possible to relieve the torque felt by the user at the ankle by keeping the sole 3 at the heel in a position substantially orthogonal to the wall 13. A stirrup 11 formed of two branches 26 connected by an arch 27 is fixed by the end of each of its branches 26 opposite to the arch to the eyelet 21 formed at each of the ends of the shaft 10. A hook 12 articulated on the arch 27 of the stirrup is inserted in a hole in the wall 13, substantially vertically in line with the hole on which the finger 4 is supported. The hole into which the hook is inserted is determined by the user so that the combined length of the stirrup 11, the hook 12 and the arms of the shaft 10 forms the hypotenuse of a right angled triangle, the right angle of which is located at the finger 4. In this way, the heel of the sole 3 is held on the wall 13 and the user can at least partially rest his weight on his heels. The stirrup 11 thus makes it possible to draw the force exerted on the heel towards the forward part of the device 1 by passing around the user's leg. The combined length of the stirrup 11, the hook 12 and the arms of the shaft 10 is preferably calculated according to the size of the device 1 so that the angle formed by the sole and the stirrup is between 45 and 60 degrees. It should be noted that during movement on the wall 13, the hook 12 and the stirrup 11 are folded one onto the other and rest on the front 25 of the upper 2 on which they can be held by an elastic device.

FIG. 8 shows a complementary arrangement making it possible to limit the lateral motion of the heel of the sole. For this purpose, two lateral tie rods 38 are fixed on the one hand to the ends of the shaft 10 on both sides of the sole 3 and on the other hand in holes 28′ in the wall 13 which are located on both sides of the longitudinal axis 22 of the sole, in the plane thereof. In this way, the heel of the sole 3 is held at the tip of an isosceles triangle, the sides of which are formed by the lateral tie rods 38, thus preventing any lateral motion. The lateral tie rods 38 each comprise a hook 12′ adapted to hook into the holes 28 in the wall 13. Each hook 12′ is connected to one end of the shaft 10 by a flexible cable 35. The length of the tie rods 38 is adapted so that the hooks 12′ can be fixed in holes 28′ spaced by at least one half-size on both sides of the toe of the sole. Of course, the flexible cables can be replaced by other non-extendible means such as straps or chains. In the same way, the hook 12 connected to the stirrup 27 can also be fixed at that location by means of a cable 35. For this reason, when the user's foot is fixed by the two tie rods 38 and the stirrup 27, it is completely immobilised with respect to the wall 13 and the user can be supported thereon for static work.

Of course, in the static position, the user can also be held on the wall 13 by means other than a belt (not shown) hooked into a hole in the wall 13 in order to leave the user's hands free to carry out the desired repair.

Reference is made to FIG. 3 to provide preferred mounting details of the finger 4 in the sole 3. The finger 4 has, in its part protruding from the sole, a substantially cylindrical shape with a diameter adapted to the dimensions of the holes 28 in the wall 13. Of course, the shape of the finger 4 can be adapted if the holes in the wall are not circular.

The finger 4 is fixedly attached to a conical body 7 cooperating with a receiver 6 having a bore of corresponding conicity so as to form a conical shank. It is known that a conicity of the order of 5% permits a quasi irreversible shank (e.g. Morse taper).

Optionally, the finger 4 can be bent downwards to avoid it slipping in the hole. In this case, the receiver 6 and the body 7 comprise a flat 8 making it possible to orientate the bend of the finger 4 when fitting the body into the receiver.

The receiver 6 is firmly fixed to the core 5 of the sole e.g. by a U-shaped reinforcement in which the receiver 6 is welded or screwed, complemented by a second reinforcement 5′ above the core 5.

In order to permit changing of the finger 4, a passage 15 is provided behind the receiver 6 in which the end of the conical body 7 opposite the finger 4 protrudes when the body 7 is fitted into the receiver. This passage 15 corresponds to an orifice 14 provided in the wear sole 18 by which it is possible to insert a cone driver to eject the body 7. Of course, other means of fixing the finger 4 can be envisaged, e.g. by screwing a threaded cylindrical body 7 into a tapped receiver 6.

Reference is made to FIG. 4 to show a detailed cross-sectional view of the heel of the sole 3. In order to recover the forces exerted on the heel by the shaft 10, the transverse housing 9 is produced in the form of a tube taken out of the sole 5 by plastic deformation, e.g. by stamping the core 5 in an omega shape, closed on itself. Other equivalent embodiments can be envisaged, e.g. producing the tube in an omega shape in a reinforcement welded under the core 5 or by welding onto the core 5 a cylindrical tube along one of the generatrices thereof. A reinforcement 5″, e.g. a metal plate, can also be fixed flat, by spot welding, on the core 5.

It can be necessary in certain cases to stiffen the sole 3 more than it can be stiffened by the core 5 which has a certain flexibility along the longitudinal axis 22. For example, in the climbing phase, the use of a very rigid sole 3, i.e. one which does not flex under the effect of the user's weight, makes it possible to return a part of the torque exerted on the toe of the foot towards the heel where it can be absorbed by the lacing or the strapping of the device 1 about the user's ankle. For this purpose, it is possible to install stiffeners in the form of angle bars parallel to the longitudinal axis of the sole, e.g. spot welded on the lower face of the core 5 and embedded in the wear sole 18. However, it is preferable, as illustrated in FIG. 9, to insert a rod forming a longitudinal stiffener 36 under the core 5 from the toe to the heel of the sole. The stiffener 36 preferably extends through the receiver 6, passes between the core 5 and the transverse housing 9 to emerge at the rear of the sole 3. The stiffener 36 is preferably located on the longitudinal middle plane of the sole. In a first embodiment illustrated in FIG. 9, the stiffener 36 extends through the receiver 6 and emerges at the rear of the sole 3 where it is fixed by a pin 37. More particularly, the stiffener 36 can be fixedly attached to the support 30, e.g. welded thereto, and can comprise a prismatic portion cooperating with the receiver 6 in a prismatic shank to ensure immobilisation of the support 30 in rotation on the longitudinal axis of the stiffener, immobilisation in translation on this axis being effected by the pin 37. According to another embodiment, the stiffener 36 is fixedly attached to the cone 7 (FIG. 3) and also emerges at the rear of the sole 3. In this case, the stiffener 36 can be used as a means for unlocking the cone when its emerging part is struck hard. At that location also, the use of a pin 37 makes it possible to ensure safety by avoiding the cone 8 being ejected by an inadvertent impact. Of course, the pin 37 can be replaced by any equivalent means, such as a retaining clip or a retaining ring or even a U-shaped staple supported in a groove provided around the stiffener 36.

In an advantageous manner, in order to facilitate moving around on walls made of perforated plates which are horizontal or of a shallow slope, e.g. less than 30 degrees, such as flat or slightly sloping roofs, the wear sole 18 comprises studs 16 having a substantially cylindrical outer shape and a central recess which is e.g. conical. Since these studs are produced in the flexible synthetic material of the sole, they deform when the wear sole 18 bears against the wall. The air contained within the recess in the stud is thus evacuated and the stud generates a suction effect if its edge rests on a continuous surface of the wall. In the case where a stud is partially resting on a hole in the wall, the flexibility of the stud can make it possible for a portion thereof to enter the hole. In this way, the adhesion of the footwear device 1 is enhanced.

However, in order to permit easy movement even over a sheet metal plate with few or no perforations, the invention makes provision that at least one stud 17 in the proximity of the heel has a smaller recess. Thus, the suction effect generated by this stud 17 is also less, permitting it to be easily detached from the surface of the wall. The traction effect exerted on the neighbouring studs 16 is then increased and the studs are detached one by one.

Of course, the central recess in each stud 16 or 17 can be of a shape other than conical, e.g. cylindrical or hemi-spherical.

As a variation, the studs 16 can be removably mounted to permit a choice of materials and shapes depending on how the device 1 is used. FIG. 10 shows an example of such as stud 16 which is screwed in a tapped housing 39 integral with the core 5 or, as appropriate, with the receiver 6. The housing 39 is in the form of a tapped cylinder which can be welded to the core 5. The stud 16 is inserted in an orifice of corresponding dimensions provided in the wear sole 18 in line with the housing 39 and can be screwed using a screw which is captive in the stud. Upon screwing of the stud, the part thereof in contact with the core 5 is crushed and swells, which makes it possible to provide sealing tightness between the stud and the wear sole.

Of course this description is given merely by way of illustrative example and a person skilled in the art could make numerous modifications thereto without departing from the scope of the invention, such as e.g. replacing the hook 12 and the stirrup 11 with straps which are adjustable or not fixed to the shaft 10, this shaft itself being able to be straight and to comprise threading at its ends on which end rings of the straps can be bolted. In the same way, in the case of an overshoe, the upper 2 can be replaced by a set of adjustable straps suitable for immobilising the foot of the user wearing the shoe on the sole 3. 

1. Footwear device (1) for moving around on walls (13) made of perforated plates, comprising an upper (2) fixedly attached to a sole (3) of flexible synthetic material, extending along a longitudinal axis (22) from a heel (24) to a toe, said sole comprising a semi-rigid plate, named core (5), integrated into the thickness of the sole, wherein said core is adapted to receive at least one rigid finger (4) able to pass into a corresponding hole (28) in the wall made of perforated plates, each finger extending at least partially along the longitudinal axis and protruding towards the forward part of the sole.
 2. Device as claimed in claim 1, wherein each finger (4) is removably mounted in the core (5) of the sole (3).
 3. Device as claimed in claim 2, wherein the finger (4) is fixed in a receiver (6) fixedly attached to the core (5) by a conical shank (7) comprising a flat (8) for orientating the finger.
 4. Device as claimed in claim 1, further comprising a plurality of fingers (4) removably and adjustably mounted on a support (30) fixedly attached to the core (5) of the sole (3).
 5. Device as claimed in claim 4, wherein the support (30) is fixed in a receiver (6) fixedly attached to the core (5) by a conical shank (7) comprising a flat (8) for orientating the support.
 6. Device as claimed in claim 1, wherein the core (5) is also suitable for forming, at the heel (24), a transverse housing (9) orthogonal to the longitudinal axis (22), issuing on both sides of the sole (3).
 7. Device as claimed in claim 6, further comprising a stirrup (11) comprising two branches (26) connected by an arch (27), said branches being respectively articulated on both sides of the sole (3) on a shaft (10) extending through the transverse housing (9), the arch of said stirrup extending over a front (25) of the upper (2).
 8. Device as claimed in claim 7, further comprising a hook (12) articulated on the arch (27) of the stirrup (11) and adapted to hook into a hole (28) in the wall (13) made of perforated plates.
 9. Device as claimed in claim 6, further comprising two lateral tie rods (38) respectively fixed to each end of the shaft (10) and adapted to be tensioned between said end and a hole (28′) in the wall (13) made of perforated plates, located substantially in a plane of the sole (3).
 10. Device as claimed in claim 9, wherein the lateral tie rods (38) have a length making it possible to fix their end in a hole (28′) located at a distance between a half-length and a length of the core (5) with respect to the longitudinal axis (22) of the sole (3).
 11. Device as claimed in claim 1, wherein the sole (3) comprises an external face, named wear sole (18), fitted with studs (16, 17) having a recess (23), which are adapted to hold the device (1) by a suction effect on a wall (13) made of perforated plates having an inclination permitting movement on the wall without use of the rigid finger (4).
 12. Device as claimed in claim 11, wherein the sole (3) comprises, at the heel (24), at least one stud (17), the recess (23) in which is made smaller so as to reduce the suction effect of said stud in order to facilitate detachment of the sole under the effect of traction.
 13. Device as claimed in claim 11, wherein the studs are removable and are fixed by screwing in tapped housings (39) integral with the core (5).
 14. Device as claimed in claim 1, wherein the sole (3) comprises a longitudinal stiffener (36) extending under the core (5) from the toe to the heel of the sole.
 15. Device as claimed in claim 1, wherein the upper (2) forms an overshoe and comprises a lace (19, 20) adapted to firmly hold a shoe in the upper.
 16. Device as claimed in claim 2, wherein the core (5) is also suitable for forming, at the heel (24), a transverse housing (9) orthogonal to the longitudinal axis (22), issuing on both sides of the sole (3).
 17. Device as claimed in claim 3, wherein the core (5) is also suitable for forming, at the heel (24), a transverse housing (9) orthogonal to the longitudinal axis (22), issuing on both sides of the sole (3).
 18. Device as claimed in claim 4, wherein the core (5) is also suitable for forming, at the heel (24), a transverse housing (9) orthogonal to the longitudinal axis (22), issuing on both sides of the sole (3).
 19. Device as claimed in claim 5, wherein the core (5) is also suitable for forming, at the heel (24), a transverse housing (9) orthogonal to the longitudinal axis (22), issuing on both sides of the sole (3).
 20. Device as claimed in claim 7, further comprising two lateral tie rods (38) respectively fixed to each end of the shaft (10) and adapted to be tensioned between said end and a hole (28′) in the wall (13) made of perforated plates, located substantially in a plane of the sole (3). 